In recent years, imposing menial work, heavy labor work, dangerous work, and work in adverse environments on industrial robots instead of human beings has been actively performed. The work carried out by this robot usually treats only fixed objects.
For that reason, development of industrial robots which can do more advanced and complicated work with respect to various objects like human beings has been expected, and researches using vision sensors or tactile sensors have been actively conducted at present. The focus of the researches is to achieve that detection of force or slip can be carried out using visual sensors or tactile sensors in order for robots to be able to exactly grip complicated-shaped objects (soft objects, objects with complicated shape, or the like) without breaking or slipping out the same.
As vision sensors used for noncontact vision sensors, existing cameras, laser scanners, or the like are put into practical use in the industrial robots in order to detect a position of a sensing object. However, these vision sensors can only detect rough position information on the object, and in addition to that, a dead angle due to the object or the robot itself poses a problem, thus they are insufficient as a sensor device that provides information required for the exact grip of the robot.
Generally, tactile sensors can obtain “more detailed information on applied force and unevenness of the object” required for the exact grip by incorporating strain gages, semiconductor pressure sensitive devices, or the like which are existing force sensors and making them directly contact to the object surface.
However, in the case of the conventional tactile sensor such as a tactile sensor described in, for example, Japanese Unexamined Patent Application Publication (Kokai) No. 2004-358634 (Patent Document 1), since the outer skin of the flexible silicone rubber is provided in the surface, wear and degradation of the sensor surface due to contact are serious, it cannot be used continuously unless human beings specially exchange the degraded main part or surface of the tactile sensor frequently, and there is a problem that personal costs may increase, so that it has not been put into practical use as industrial use. In addition, that the focus of the current tactile sensor researches is directed to the development of new devices so as to enhance sensing capabilities is also a reason why the practical application has not been achieved.
Meanwhile, a tactile sensor is one of the elements required to make a robot perform operations of the complicated-shaped objects and soft objects that only human beings could do until now. As one of the extensive applications of this tactile sensor, there is an industrial robot system utilized in a recycling system which automates the work of separating the garbage.
Circulation of resources based on recycling is one of critical issues in the industry at present, but when recycling work is done by human beings putting it on an operating base poses a difficult problem in consideration labor costs and safety. Accordingly, when considering making the industrial robot work the separation work of the garbage in the automated recycling system, it can be assumed the work of performing the separation in which the robot is made to find the specific garbage among various types of garbage using a simple image processing and to pick it up. In such an application, although it is possible to make the industrial robot find out the specific garbage, the work to exactly pick up the garbage with various shapes has been a technically difficult problem in the conventional technologies.    [Patent Document 1] Japanese Unexamined Patent Application Publication (Kokai) No. 2004-358634